An experimental study of a freeze-thaw damage model of natural pumice concrete

摘要

This paper presents the experimental studies of the natural pumice concrete freeze-thaw damage model based on Cai Hao's Model and Powers' hydrostatic pressure hypothesis. The hydrostatic pressure calculation and testing methods are improved by the application of a theory of fatigue damage mechanics and a more accurate description of the physical properties of natural pumice concrete. A hydrostatic pressure calculation model was established for natural pumice concrete through simplification of the system. The model was then verified by experiments. Cryogenic nuclear magnetic resonance (NMR) was then applied to samples. Finally, a freeze-thaw damage model for natural pumice concrete was developed. The experimental results indicate that the freeze-thaw damage model, which uses the relative dynamic modulus of the elasticity loss Dof the natural pumice concrete as a physical damage index, can effectively provide theoretical support for the study of freeze-thaw damage mechanisms affecting natural pumice concrete. (C) 2018 Elsevier B.V. All rights reserved.